Phase 2 Study to Determine if RTB101 Reduces the Severity of COVID-19 in Older Adults Residing in Nursing Homes

Inclusion Criteria: * Informed consent must be obtained from the subject or health care proxy before any assessment is performed. * Adults (male and female) aged 65 years and over. * Residing in a nursing home in which one or more residents or staff has developed laboratory-confirmed symptomatic COVID-19 infection at the time of randomization Exclusion Criteria: Subjects will not be eligible if they meet any of the following criteria: * Any subject who is a current smoker or has a ≥ 10 pack year smoking history. * Subjects with a medical history of chronic obstructive pulmonary disease (COPD). * Subjects who are in hospice or receiving comfort care only. * Subjects who have symptomatic laboratory-confirmed COVID-19 at the time of screening or randomization. * Subjects with current evidence of an unstable medical disorder including an unstable respiratory disorder, gastrointestinal disorder (including Child-Pugh class B and C hepatic impairment), renal disorder (including subjects with an estimated glomerular filtration rate (eGFR) ≤30 mL/min/1.73m2), or hematologic disorder (including active leukemia). * Subjects receiving immunosuppressive therapy including chronic use of prednisone \>10 mg daily (however, inhaled corticosteroids and acute use of higher doses of prednisone to treat conditions such as exacerbation of asthma or other acute conditions are allowed). * Subjects with an immunodeficiency disease, including a positive human immunodeficiency virus (HIV) test result. * Sexually active males with a partner of child-bearing potential